In vitro evaluation of the cytotoxicity and eye irritation potential of preservatives widely used in cosmetics

Abstract The consumption of cosmetics has been increasing every year and is expected to reach $675 billion by 2020 at an estimated growth rate of 6.4% per year. Exposure to skin irritants is the major cause of non-immunological inflammation of the skin. Therefore, the safety evaluation of cosmetic preservatives should be increased. Thus, the present work aimed to evaluate the cytotoxicity as the viability endpoint and the eye irritation potential of preservatives used in cosmetics. Cytotoxicity assays were performed using MTT and NRU in human keratinocytes (HaCaT), human dermal fibroblasts, adult (HDFa), and human hepatoma cells (HepG2). The eye irritation potential was evaluated using the Hen's Egg Test-chorioallantoic membrane (HET-CAM). The evaluated preservatives were methylparaben (MP), propylparaben (PP), phenoxyethanol (PE), and a mixture of methylchloroisothiazolinone and methylisothiazolinone (CMI/MI). All preservatives showed cytotoxic potential within the permitted concentrations for use in cosmetic products. In the HET-CAM test, PE and CMI/MI, MP, and PP were classified as severe, moderate, and poor irritants, respectively. Our results indicate that proper safety evaluations are required to ensure the beneficial properties of preservatives on cosmetic products without exceeding exposure levels that would result in adverse health effects for consumers.

New and potential properties, characteristics, and analytical methods of ferulic acid: A review

Abstract Phenolic compounds are widely distributed in the plant kingdom and in the microorganisms. Cinnamic acid and its hydroxylated derivative-ferulic acid, are phenolic compounds. Ferulic acid possesses antioxidant potential, as well as anti-cancer, anti-inflammatory, and antimicrobial properties. It prevents the harmful effects of radiation both as an ultraviolet absorber and as a free radical scavenger; it is not cytotoxic. Although ferulic acid has beneficial properties, it is hardly used in cosmetic preparations and has been rarely studied in the literature. Herein, we review the literature on ferulic acid, to provide information which can contribute to further research on the compound.

Guava: phytochemical composition of a potential source of antioxidants for cosmetic and/or dermatological applications

ABSTRACT Guava (Psidium guajava L.) is a native fruit of the American tropics with commercial applications for its taste, flavor and aroma. Numerous pharmacological uses have been described for it, such as the antiseptic effect of its leaves, the use of the fresh fruit and tea from its leaves for the treatment of diarrhea, dysentery, diabetes mellitus, and others. However, considering its rich composition, the guava also is a potential source of antioxidants to be used in the development of new formulations for cosmetic and/or dermatological applications, the main focus of this research. Herein, we describe the study of the phytochemical composition and the antioxidant activity of a guava extract prepared with non-toxic solvents aiming its use at biological applications. High performance liquid chromatography and mass spectrometry were employed to identify the major components, while thermoanalytical measurements and hot stage microscopy were used to assess the chemical stability of guava fruit extract. The antioxidant activity was also evaluated assessing the SOD-like activity and ABTS free radical scavenger. The results show that the extract is a rich source of phenolic compounds, such as quercetin, kaempferol, schottenol, among many others. All of the components found in guava extract exhibit biological effects according to the literature data, mainly antioxidant properties.

Development and evaluation of an emulsion containing lycopene for combating acceleration of skin aging

Lycopene, a carotenoid and potent antioxidant is found in large quantities in tomatoes. Lycopene combats diseases, such as cardiovascular disease and different types of cancer, including prostate cancer. However, its topical use in emulsion form for the combat of skin aging is under-explored. The aim of the present study was to develop an emulsion containing lycopene extracted from salad tomatoes and evaluate its cytotoxicity, stability, rheological behavior, antioxidant activity and phytocosmetic permeation. The developed cosmetic comprised an oil phase made up of shea derivatives and was evaluated in terms of its physiochemical stability, spreadability, thermal analysis, rheological behavior, microbiological quality, cytotoxicity, antioxidant activity, cutaneous permeation and retention. The results demonstrate that this phytocosmetic is stable, exhibits satisfactory rheological behavior for a topical formula and is a promising product for combating skin aging.

Licopeno é um carotenóide com potente atividade antioxidante encontrado em grande quantidade no tomate e usado no combate a diversas doenças como doenças cardiovasculares e diferentes tipos de cânceres, incluindo o câncer de próstata. O objetivo desse trabalho foi desenvolver uma emulsão contendo extrato de licopeno obtido do tomate salada e avaliar a citotoxicidade do extrato, a estabilidade, o comportamento reológico, atividade antioxidante e permeação do fitocosmético. O cosmético foi desenvolvido utilizando fase oleosa contendo derivados de Karité e submetido à avaliação da estabilidade físico-química, espalhabilidade, análise térmica, comportamento reológico, qualidade microbiológica, citotoxicidade, atividade antioxidante e testes de permeação e retenção cutânea. Os resultados demonstraram que o fitocosmético é estável, apresenta comportamento reológico desejável para uma formulação tópica e é um produto promissor para ser utilizado no combate à aceleração do envelhecimento cutâneo.

Estudo da segurança de cosméticos: presente e futuro / Study of the safety of cosmetics: present and future

Cosméticos são usados pelo homem desde a antiguidade e, atualmente, o consumo tem aumentado muito, inclusive no Brasil, o terceiro maior mercado no mundo. Assim sendo, a preocupação com a segurança e eficácia destes produtos deve ser intensificada, mesmo sendo produtos raramente relacionados a reações adversas que causem danos à saúde. Para a avaliação das possíveis reações que podem ser apresentadas pelos produtos (irritação, sensibilização, efeitos sistêmicos), a Legislação Brasileira exige que os fabricantes avaliem a segurança e eficácia de seus produtos. Para este fim, em geral, são utilizados animais como modelo experimental o que está sendo cada vez mais evitado, acarretando a pesquisa por métodos alternativos para estas avaliações, que não necessitem de modelos experimentais in vivo. Desta forma, a presente revisão tem por objetivo apresentar os principais ensaios biológicos utilizados para avaliação da segurança de cosméticos, bem como ensaios in vitro que os substituam.

Cosmetics have been used since ancient times and, recently, their consumption has increased greatly in many countries, including brazil, which is the third largest consumer market in the world. Thus, concern for the safety and efficacy of these products should be heightened, even though these products are rarely related to adverse reactions that damage the health. Brazilian law requires manufacturers to subject their products to safety testing, to assess the possible reactions that could be caused by them (irritation, sensitization, systemic effects). To this end, in general, animals have been used as the experimental model, but this practice is being increasingly controlled, so that the scientific community is looking for alternative tests that do not require experimental in vivo models. Thus, this review aims to describe the main biological assays used to assess the safety of cosmetics, as well as in vitro assays that can replace them.

Design of antiseptic formulations containing extract of Plinia cauliflora / Concepção de formulações anti-sépticas que contenham extrato de Plinia cauliflora

The leaves of the Brazilian species Plinia cauliflora were used to obtain active hydroalcoholic extract and fractions enabling the development of efficient antiseptic pharmaceutical formulations. A chemical composition of 70 percent ethanol extract, aqueous and ethyl acetate fractions was analyzed by thin-layer chromatography and for phenol content. Antimicrobial activity was tested against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Lactobacillus acidophilus and Candida albicans by the agar diffusion method and the minimum inhibitory concentration was assayed by broth microdilution. Extract microbiological quality was tested to avoid contamination in the formulations. A mouthwash and a topical cream containing the extract were developed and antiseptic activity was assessed by agar diffusion. Sensory and physicochemical stability of the formulations were assayed. Chromatography indicated the presence of terpenes, flavonoids and tannins in the extract and fractions and total phenol content were found to be high. The plant samples were active against all the microorganisms tested, except for Lactobacillus acidophilus. Both topical formulations showed antiseptic activity and stability. Thus, these may be used as antimicrobials in skin infections, but would be more useful in the treatment of candidiasis.

As folhas da espécie brasileira Plinia cauliflora foram utilizadas a fim de se obter um extrato hidroalcoólico e frações ativas proporcionando o desenvolvimento de eficazes formulações farmacêuticas antissépticas. A composição química do extrato etanólico 70 por cento, fração aquosa e acetato de etila foi analisada por cromatografia em camada delgada e teor de fenóis. A atividade antimicrobiana foi testada frente a Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Lactobacillus acidophilus e Candida albicans por difusão em ágar e a concentração inibitória mínima foi determinada por microdiluição. A qualidade microbiológica do extrato foi avaliada para evitar a contaminação das formulações. Foram desenvolvidos um enxaguatório bucal e um creme tópico contendo o extrato sendo que a atividade antisséptica foi ensaiada por difusão em ágar. A estabilidade sensorial e físico-química foram testadas. A cromatografia indicou a presença de terpenos, flavonóides e taninos no extrato e frações, observando-se alto teor de fenóis totais. As amostras vegetais foram ativas contra todos os micro-organismos testados, exceto Lactobacillus acidophilus. Ambas as formulações apresentaram atividade antisséptica e estabilidade. Desta forma, infere-se que as formulações desenvolvidas podem ser utilizadas como antissépticas em infecções de pele, podendo ser mais eficazes no tratamento de candidíase.